SiC宽禁带功率放大器的设计与实践

介绍了SiC宽禁带功率器件的特性,与Si功率器件相比,该器件在输出功率、功率密度、工作频率、工作带宽、环境适应性、抗辐射能力等方面有卓越的性能.利用SiC宽禁带功率器件设计制作了L波段100W功率放大器.对SiC宽禁带功率放大器进行性能测试和环境实验,分析了SiC宽禁带功率器件的性能特点和优势.SiC宽禁带功率器件有利于提高功率放大器的工作带宽,改善功率放大器的环境适应性.     

1kW宽带线性SiC功率放大器设计

简述了SiC宽禁带半导体材料的特性,通过与传统Si半导体材料相比较,该材料在击穿电场强度、截止频率、热传导率、抗辐射能力、结温和热稳定性等方面具有明显优势。SiC宽禁带功率器件在输出功率、功率密度、工作频率、环境适应性等方面具有卓越的性能,在雷达发射机中有良好的应用前景。文中利用SiC宽禁带功率器件设计制作了L波段1 kW功率放大器,对SiC宽禁带功率放大器进行了性能测试,根据实验数据分析了SiC宽禁带功率器件对固态雷达发射机性能的改善。     

SiC宽禁带功率器件在雷达发射机中的应用分析

介绍了SiC宽禁带半导体材料的特性,通过与Si和GaAs半导体相比较,该材料在击穿电场强度、截止频率、热传导率、抗辐射能力、结温和热稳定性等方面具有显著优点。SiC宽禁带功率器件,尤其在输出功率、功率密度、工作频率、工作带宽、环境适应性和总效率等方面具有卓越的性能,在雷达发射机中有良好的应用前景。文章还详细论述了现代雷达对SiC功率器件的具体指标要求。     

SiC微波半导体在T/R组件中的应用

本文简述了SiC微波半导体的特性,分析了SiC微波器件在有源相控阵雷达T/R组件中的应用,讨论了T/R组件微波关键技术,即功率放大链、高功率限幅保护、低噪声接收机前端等微波半导体电路的设计思路以及SiC微波器件在T/R组件中的潜在应用,比较了Si和SiC时代关键电路的特性及其技术状态,指出了SiC微波半导体的发展对未来军事电子设备相控阵雷达T/R组件的重要性。     

SiC宽带功率放大器模块设计分析

功率放大器是射频前端中的关键部件,宽带是目前功率放大器的主要发展趋势。基于碳化硅(SiC)宽禁带功率器件,利用ADS仿真软件,依据宽带功率放大器的各项指标进行电路的设计、优化和仿真,制作了500~2 000 MHz波段宽带功率放大器,并对放大器进行了性能测试和环境实验。测试结果表明利用该方法设计宽带功率放大器是可行的,SiC宽禁带功率器件具有较宽的工作带宽。     

三代半导体功率器件的特点与应用分析

以S i双极型功率晶体管为代表的第一代半导体功率器件和以GaAs场效应晶体管为代表的第二代半导体功率器件为雷达发射机的大规模固态化和可靠性提高做出了贡献。近年来以S iC场效应功率晶体管和GaN高电子迁移率功率晶体管为代表的第三代半导体--宽禁带半导体功率器件具有击穿电压高、功率密度高、输出功率高、工作效率高、工作频率高、瞬时带宽宽、适合在高温环境下工作和抗辐射能力强等优点。人们寄希望于宽禁带半导体功率器件来解决第一代、第二代功率器件的输出功率低、效率低和工作频率有局限性以至于无法满足现代雷达、电子对抗和通信等电子装备需求等方面的问题。文中简要介绍了半导体功率器件的发展背景、发展过程、分类、特点、应用、主要性能参数和几种常用的半导体功率器件;重点叙述了宽禁带半导体功率器件的特点、优势、研究进展和工程应用;对宽禁带半导体功率器件在新一代雷达中的应用前景和要求进行了探讨。     

SiC微波半导体在T／R组件中的应用前景

简述了SiC微波半导体的特性,通过与Si相关特性的比较,SiC在击穿电压、热传导率、增益特性等方面具有的显著优势,分析了SiC微波器件在有源相控阵雷达T/R组件中的应用前景,对T/R组件微波关键技术,功率放大链、高功率限幅器、低噪声接收机前端等微波半导体电路的设计思路进行了讨论,及SiC微波器件在T/R组件中的潜在应用,比较了Si和SiC时代,关键电路的特性及其技术状态,以及对未来军事电子设备相控阵雷达T/R组件发展的重要性.     

宽禁带半导体SiC功率器件发展现状及展望

碳化硅(SiC)是第三代半导体材料的典型代表,也是目前晶体生长技术和器件制造水平最成熟、应用最广泛的宽禁带半导体材料之一,是高温、高频、抗辐照、大功率应用场合下极为理想的半导体材料.文章结合美国国防先进研究计划局DARPA的高功率电子器件应用宽禁带技术HPE项目的发展,介绍了SiC功率器件的最新进展及其面临的挑战和发展前景.同时对我国宽禁带半导体SiC器件的研究现状及未来的发展方向做了概述与展望.     

碳化硅器件发展概述

概要介绍了第三代半导体材料碳化硅(SiC)在高温、高频、大功率器件应用方面的优势,结合国际上SiC肖特基势垒二极管,PiN二极管和结势垒肖特基二极管的发展历史,介绍了SiC功率二极管的最新进展,同时对我国宽禁带半导体SiC器件的研究现状及发展方向做了概述及展望。     

S波段系列SiC MESFET器件研制

SiC材料具有宽禁带、高电子饱和漂移速度、高击穿电压、高热导率和相对低的介电常数等优点,使SiC MESFET在微波功率等方面的应用得到了快速发展。采用国产SiC外延片,解决了欧姆接触、干法刻蚀及损伤修复等一系列工艺难题;针对不同应用背景,研制出总栅宽分别为1、5、15、20mm系列SiC MESFET样管。在2GHz脉冲状态下,300μs脉宽、10%占空比、20mm栅宽器件单胞输出功率超过80W,功率密度大于4W/mm;15mm栅宽器件在3.1~3.4GHz频带脉冲功率输出超过30W。该研究结果为SiC器件的实用化奠定了基础。     

Technology innovation and process integrations for sub-100nm gate patterning

This paper presents a brief overview of the Applied Centura(R)DPS(R)system,configured with silicon etch DPS Ⅱ chamber, with emphasis on discussing tuning capability for CD uniformity control. It also presents the studies of etch process chemistry and film integration impact for an overall successful gate patterning development. Discussions will focus on resolutions to key issues, such as CD uniformity, line-edge roughness, and multilayer film etching integration.     

White organic light-emitting devices based on fac tris（2- phenylpyridine） iridium sensitized 5,6,11,12-tetraphenylnap -hthacene

We have fabricated the white organic light-emitting devices （WOLEDs） based on 4,4＇ -bis（2,2 -diphenyl vinyl）-1,1＇ - biphenyl （DPVBi） and phosphorescence sensitized 5,6,11,12,-tetraphenylnaphthacene （rubrene）. The device structure is ITO/2T-NATA （20 nm）/NPBX （20 nm）/CBP： x%Ir（ppy）3：0.5% rubrene （8 nm）/NPBX （5 nm）/DPVBi （30 nm）/Alq（30 nm）/LiF（0.5 nm）/A1. In the devices, DPVBi acts as a blue light-emitting layer, the rubrene is sensitized by a phosphorescent material, fac tris （2-phenylpyridine） iridium [Ir（ppy）3], acts as a yellow light-emitting layer, and N,N＇ -bis- （1-naphthyl）- N,N＇ -diphenyl -1, 1＇ -biphenyl-4,4＇ -diamine （NPBX） acts as a hole transporting and exciton blocker layer, respectively. When the concentration of Ir （PPY）3 is 6wt%, the maximum luminance is 24960 cd/m^2 at an applied voltage of 15 V, and the maximum luminous efficiency is 5.17 cd/A at an applied voltage of 8 V.     

Complete approach to automatic identification and subpixel center location for ellipse feature

To meet the need of automatic image features extraction with high precision in visual inspection, a complete approach to automatic identification and sub-pixel center location for similar-ellipse feature is proposed. In the method, the feature area is identified automatically based on the edge attribute, and the sub-pixel center location is accomplished with the leastsquare algorithm. It shows that the method is valid, practical, and has high precision by experiment. Meanwhile this method can meet the need of instrumentation of visual inspection because of easy realization and without man-machine interaction.     

小角度扩展相关性近似算法分析

本论文提出一种在多天线MIMO信道相关性建模中小角度扩展近似理论算法,并应用于分析MIMO系统性能。分析中分别对三种不同角能量分布情况下的空间相关性研发快速近似计算法,并同时提出双模(Bi-Modal)角能量分布情况下的近似运算。通过分析这些新方法的近似效率,可以得到计算简单、复杂度低、而且符合实际的MIMO相关信道矩阵,对系统级的快速高效计算法的研究和系统级的评估以及误差分析具有重要的意义。     

Curved crystal spectrometer for the measurement of X-ray lines from laser-produced plasmas

In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal （200） （2d = 0.4027 nm） is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line（w）, the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line（x）, the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines（y）, the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line（z） in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line（q） in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution（λ/△ 2） is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.     

A Versatile Mixed-Signal Pin Approach for Cost-Effective Test of Automotive ICs

Integrated circuits (ICs) intended for increasingly sophisticated automotive applications bring unique test demands. Advanced ICs for applications such as highly integrated automatic braking system (ABS) and airbag controllers combine high voltage digital channels, significant VI demands and precise timing capability. Along with continued missioncritical reliability concerns, the trend toward higher voltage operation and increased device integration requires specialized test capabilities able to extend across the wide operating ranges found in automotive applications. Among these capabilities, automotive test requirements increasingly dictate a need for a cost-effective versatile mixed-signal pin electronics with very high data rates reaching up to 50MHz with a voltage swing of-2 V to +28 V.     

Electronic Structure of Semiconductor Nanocrystals

This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.     

Critical Stage Rule-Based Real Time Dispatch（RTD）System in Highly-Mixed-Products （HMP） FAB

An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.     

Optical vibration and deviation measurement of rotating machine parts

It is of interest to get appropriate information about the dynamic behaviour of rotating machinery parts in service. This paper presents an approach of optical vibration and deviation measurement of such parts. Essential of this method is an image derotator combined with a high speed camera or a laser doppler vibrometer （LDV）.